A vehicle such as an electric automobile or a hybrid automobile is equipped with an electric power converter that performs power conversion between direct-current power and alternating-current power. For example, PTL 1 listed below discloses an electric power converter that includes a semiconductor module with a built-in semiconductor element and a plurality of electronic circuit boards. The plurality of electronic circuit boards includes a first electronic circuit board for high-voltage system and a second electronic circuit board for low-voltage system. The first electronic circuit board and the second electronic circuit board are stacked with a space therebetween in a board thickness direction and are fixed to a fixation surface of a container that contains the semiconductor module. Such stacking arrangement is effective in reducing the sizes of the electronic circuit boards along their plate surfaces.